1
|
Zhou CM, Jiang ZZ, Liu N, Yu XJ. Current insights into human pathogenic phenuiviruses and the host immune system. Virulence 2024; 15:2384563. [PMID: 39072499 PMCID: PMC11290763 DOI: 10.1080/21505594.2024.2384563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 07/09/2024] [Accepted: 07/18/2024] [Indexed: 07/30/2024] Open
Abstract
Phenuiviruses are a class of segmented negative-sense single-stranded RNA viruses, typically consisting of three RNA segments that encode four distinct proteins. The emergence of pathogenic phenuivirus strains, such as Rift Valley fever phlebovirus (RVFV) in sub-Saharan Africa, Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) in East and Southeast Asia, and Heartland Virus (HRTV) in the United States has presented considerable challenges to global public health in recent years. The innate immune system plays a crucial role as the initial defense mechanism of the host against invading pathogens. In addition to continued research aimed at elucidating the epidemiological characteristics of phenuivirus, significant advancements have been made in investigating its viral virulence factors (glycoprotein, non-structural protein, and nucleoprotein) and potential host-pathogen interactions. Specifically, efforts have focused on understanding mechanisms of viral immune evasion, viral assembly and egress, and host immune networks involving immune cells, programmed cell death, inflammation, nucleic acid receptors, etc. Furthermore, a plethora of technological advancements, including metagenomics, metabolomics, single-cell transcriptomics, proteomics, gene editing, monoclonal antibodies, and vaccines, have been utilized to further our understanding of phenuivirus pathogenesis and host immune responses. Hence, this review aims to provide a comprehensive overview of the current understanding of the mechanisms of host recognition, viral immune evasion, and potential therapeutic approaches during human pathogenic phenuivirus infections focusing particularly on RVFV and SFTSV.
Collapse
Affiliation(s)
- Chuan-Min Zhou
- Gastrointestinal Disease Diagnosis and Treatment Center, The First Hospital of Hebei Medical University, Shijiazhuang, China
- Department of General Surgery, Hebei Key Laboratory of Colorectal Cancer Precision Diagnosis and Treatment, The First Hospital of Hebei Medical University, Shijiazhuang, China
- Central Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, China
| | - Ze-Zheng Jiang
- State Key Laboratory of Virology, School of Public Health, Wuhan University, Wuhan, China
| | - Ning Liu
- Department of Quality and Operations Management, The First Hospital of Hebei Medical University, Shijiazhuang, China
| | - Xue-Jie Yu
- State Key Laboratory of Virology, School of Public Health, Wuhan University, Wuhan, China
| |
Collapse
|
2
|
Uckeley ZM, Duboeuf M, Gu Y, Erny A, Mazelier M, Lüchtenborg C, Winter SL, Schad P, Mathieu C, Koch J, Boulant S, Chlanda P, Maisse C, Brügger B, Lozach PY. Glucosylceramide in bunyavirus particles is essential for virus binding to host cells. Cell Mol Life Sci 2024; 81:71. [PMID: 38300320 PMCID: PMC10834583 DOI: 10.1007/s00018-023-05103-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 12/08/2023] [Accepted: 12/21/2023] [Indexed: 02/02/2024]
Abstract
Hexosylceramides (HexCer) are implicated in the infection process of various pathogens. However, the molecular and cellular functions of HexCer in infectious cycles are poorly understood. Investigating the enveloped virus Uukuniemi (UUKV), a bunyavirus of the Phenuiviridae family, we performed a lipidomic analysis with mass spectrometry and determined the lipidome of both infected cells and derived virions. We found that UUKV alters the processing of HexCer to glycosphingolipids (GSL) in infected cells. The infection resulted in the overexpression of glucosylceramide (GlcCer) synthase (UGCG) and the specific accumulation of GlcCer and its subsequent incorporation into viral progeny. UUKV and several pathogenic bunyaviruses relied on GlcCer in the viral envelope for binding to various host cell types. Overall, our results indicate that GlcCer is a structural determinant of virions crucial for bunyavirus infectivity. This study also highlights the importance of glycolipids on virions in facilitating interactions with host cell receptors and infectious entry of enveloped viruses.
Collapse
Affiliation(s)
- Zina M Uckeley
- Center for Integrative Infectious Diseases Research (CIID), University Hospital Heidelberg, 69120, Heidelberg, Germany
- Cluster of Excellence, CellNetworks, 69120, Heidelberg, Germany
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany
- Department for Molecular Genetics and Microbiology, University of Florida, Gainesville, USA
| | - Maëva Duboeuf
- Université Claude Bernard Lyon 1, INRAE, EPHE, IVPC UMR754, Team iWays, 69007, Lyon, France
| | - Yu Gu
- Université Claude Bernard Lyon 1, INRAE, EPHE, IVPC UMR754, Team iWays, 69007, Lyon, France
| | - Alexandra Erny
- Université Claude Bernard Lyon 1, INRAE, EPHE, IVPC UMR754, Team iWays, 69007, Lyon, France
| | - Magalie Mazelier
- Center for Integrative Infectious Diseases Research (CIID), University Hospital Heidelberg, 69120, Heidelberg, Germany
- Cluster of Excellence, CellNetworks, 69120, Heidelberg, Germany
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany
| | | | - Sophie L Winter
- Center for Integrative Infectious Diseases Research (CIID), University Hospital Heidelberg, 69120, Heidelberg, Germany
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany
- Schaller Research Groups, Department of Infectious Diseases, Virology, Heidelberg University Hospital, Heidelberg, Germany
| | - Paulina Schad
- Center for Integrative Infectious Diseases Research (CIID), University Hospital Heidelberg, 69120, Heidelberg, Germany
- Cluster of Excellence, CellNetworks, 69120, Heidelberg, Germany
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany
| | - Cyrille Mathieu
- CIRI (Centre International de Recherche en Infectiologie), Team Neuro-Invasion, TROpism and VIRal Encephalitis, INSERM U1111, CNRS UMR5308, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, 69007, Lyon, France
| | - Jana Koch
- Center for Integrative Infectious Diseases Research (CIID), University Hospital Heidelberg, 69120, Heidelberg, Germany
- Cluster of Excellence, CellNetworks, 69120, Heidelberg, Germany
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany
- Université Claude Bernard Lyon 1, INRAE, EPHE, IVPC UMR754, Team iWays, 69007, Lyon, France
| | - Steeve Boulant
- Department for Molecular Genetics and Microbiology, University of Florida, Gainesville, USA
| | - Petr Chlanda
- Center for Integrative Infectious Diseases Research (CIID), University Hospital Heidelberg, 69120, Heidelberg, Germany
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany
- Schaller Research Groups, Department of Infectious Diseases, Virology, Heidelberg University Hospital, Heidelberg, Germany
| | - Carine Maisse
- Université Claude Bernard Lyon 1, INRAE, EPHE, IVPC UMR754, Team iWays, 69007, Lyon, France
| | - Britta Brügger
- Heidelberg University Biochemistry Center (BZH), Heidelberg, Germany
| | - Pierre-Yves Lozach
- Center for Integrative Infectious Diseases Research (CIID), University Hospital Heidelberg, 69120, Heidelberg, Germany.
- Cluster of Excellence, CellNetworks, 69120, Heidelberg, Germany.
- Department of Infectious Diseases, Virology, University Hospital Heidelberg, 69120, Heidelberg, Germany.
- Université Claude Bernard Lyon 1, INRAE, EPHE, IVPC UMR754, Team iWays, 69007, Lyon, France.
| |
Collapse
|
3
|
Boshra H. An Overview of the Infectious Cycle of Bunyaviruses. Viruses 2022; 14:v14102139. [PMID: 36298693 PMCID: PMC9610998 DOI: 10.3390/v14102139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/19/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022] Open
Abstract
Bunyaviruses represent the largest group of RNA viruses and are the causative agent of a variety of febrile and hemorrhagic illnesses. Originally characterized as a single serotype in Africa, the number of described bunyaviruses now exceeds over 500, with its presence detected around the world. These predominantly tri-segmented, single-stranded RNA viruses are transmitted primarily through arthropod and rodent vectors and can infect a wide variety of animals and plants. Although encoding for a small number of proteins, these viruses can inflict potentially fatal disease outcomes and have even developed strategies to suppress the innate antiviral immune mechanisms of the infected host. This short review will attempt to provide an overall description of the order Bunyavirales, describing the mechanisms behind their infection, replication, and their evasion of the host immune response. Furthermore, the historical context of these viruses will be presented, starting from their original discovery almost 80 years ago to the most recent research pertaining to viral replication and host immune response.
Collapse
Affiliation(s)
- Hani Boshra
- Global Urgent and Advanced Research and Development (GUARD), 911 Rue Principale, Batiscan, QC G0X 1A0, Canada
| |
Collapse
|
4
|
Moalem Y, Malis Y, Voloshin K, Dukhovny A, Hirschberg K, Sklan EH. Sandfly Fever Viruses Attenuate the Type I Interferon Response by Targeting the Phosphorylation of JAK-STAT Components. Front Immunol 2022; 13:865797. [PMID: 35720342 PMCID: PMC9198438 DOI: 10.3389/fimmu.2022.865797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 05/09/2022] [Indexed: 11/25/2022] Open
Abstract
Sandfly fever viruses are emerging Phleboviruses typically causing mild febrile illness. Some strains, however, can cause severe and occasionally fatal neuro-invasive disease. Like most viruses, Phleboviruses have devised various strategies to inhibit the type I interferon (IFN) response to support a productive infection. Still, most of the strategies identified so far focus on inhibiting the sensing arm of the IFN response. In contrast, the effect of sandfly virus infection on signaling from the IFN receptor is less characterized. Therefore, we tested the effect of sandfly fever virus Naples (SFNV) and Sicily (SFSV) infection on IFN signaling. We found that infection with either of these viruses inhibits signaling from the IFN receptor by inhibiting STAT1 phosphorylation and nuclear localization. We show that the viral nonstructural protein NSs mediates these effects, but only NSs from SFNV was found to interact with STAT1 directly. Thus, we tested the upstream IFN signaling components and found that Janus kinase 1 (Jak1) phosphorylation is also impaired by infection. Furthermore, the NSs proteins from both viruses directly interacted with Jak1. Last, we show that IFN inhibition by SFNV and SFSV is most likely downstream of the IFN receptor at the Jak1 level. Overall, our results reveal the multiple strategies used by these related viruses to overcome host defenses.
Collapse
Affiliation(s)
- Yarden Moalem
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yehonathan Malis
- Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Konstantin Voloshin
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Anna Dukhovny
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Koret Hirschberg
- Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ella H Sklan
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
5
|
Xu L, Li X, Gao X, Liu S, Pang Z, Wang Z. Viral suppression of type I interferon signaling by NSs proteins of DBV, SFSV and UUKV via NSs-mediated RIG-I degradation. BIOSAFETY AND HEALTH 2022. [DOI: 10.1016/j.bsheal.2022.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
|
6
|
Ren F, Shen S, Wang Q, Wei G, Huang C, Wang H, Ning YJ, Zhang DY, Deng F. Recent Advances in Bunyavirus Reverse Genetics Research: Systems Development, Applications, and Future Perspectives. Front Microbiol 2021; 12:771934. [PMID: 34950119 PMCID: PMC8689132 DOI: 10.3389/fmicb.2021.771934] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/03/2021] [Indexed: 12/25/2022] Open
Abstract
Bunyaviruses are members of the Bunyavirales order, which is the largest group of RNA viruses, comprising 12 families, including a large group of emerging and re-emerging viruses. These viruses can infect a wide variety of species worldwide, such as arthropods, protozoans, plants, animals, and humans, and pose substantial threats to the public. In view of the fact that a better understanding of the life cycle of a highly pathogenic virus is often a precondition for developing vaccines and antivirals, it is urgent to develop powerful tools to unravel the molecular basis of the pathogenesis. However, biosafety level −3 or even −4 containment laboratory is considered as a necessary condition for working with a number of bunyaviruses, which has hampered various studies. Reverse genetics systems, including minigenome (MG), infectious virus-like particle (iVLP), and infectious full-length clone (IFLC) systems, are capable of recapitulating some or all steps of the viral replication cycle; among these, the MG and iVLP systems have been very convenient and effective tools, allowing researchers to manipulate the genome segments of pathogenic viruses at lower biocontainment to investigate the viral genome transcription, replication, virus entry, and budding. The IFLC system is generally developed based on the MG or iVLP systems, which have facilitated the generation of recombinant infectious viruses. The MG, iVLP, and IFLC systems have been successfully developed for some important bunyaviruses and have been widely employed as powerful tools to investigate the viral replication cycle, virus–host interactions, virus pathogenesis, and virus evolutionary process. The majority of bunyaviruses is generally enveloped negative-strand RNA viruses with two to six genome segments, of which the viruses with bipartite and tripartite genome segments have mostly been characterized. This review aimed to summarize current knowledge on reverse genetic studies of representative bunyaviruses causing severe diseases in humans and animals, which will contribute to the better understanding of the bunyavirus replication cycle and provide some hints for developing designed antivirals.
Collapse
Affiliation(s)
- Fuli Ren
- Research Center for Translational Medicine, Wuhan Jinyintan Hospital, Wuhan, China.,State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Shu Shen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Qiongya Wang
- Research Center for Translational Medicine, Wuhan Jinyintan Hospital, Wuhan, China
| | - Gang Wei
- Research Center for Translational Medicine, Wuhan Jinyintan Hospital, Wuhan, China
| | - Chaolin Huang
- Research Center for Translational Medicine, Wuhan Jinyintan Hospital, Wuhan, China
| | - Hualin Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Yun-Jia Ning
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Ding-Yu Zhang
- Research Center for Translational Medicine, Wuhan Jinyintan Hospital, Wuhan, China
| | - Fei Deng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| |
Collapse
|
7
|
Host Cell Restriction Factors of Bunyaviruses and Viral Countermeasures. Viruses 2021; 13:v13050784. [PMID: 33925004 PMCID: PMC8146327 DOI: 10.3390/v13050784] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/14/2021] [Accepted: 04/20/2021] [Indexed: 01/01/2023] Open
Abstract
The Bunyavirales order comprises more than 500 viruses (generally defined as bunyaviruses) classified into 12 families. Some of these are highly pathogenic viruses infecting different hosts, including humans, mammals, reptiles, arthropods, birds, and/or plants. Host cell sensing of infection activates the innate immune system that aims at inhibiting viral replication and propagation. Upon recognition of pathogen-associated molecular patterns (PAMPs) by cellular pattern recognition receptors (PRRs), numerous signaling cascades are activated, leading to the production of interferons (IFNs). IFNs act in an autocrine and paracrine manner to establish an antiviral state by inducing the expression of hundreds of IFN-stimulated genes (ISGs). Some of these ISGs are known to restrict bunyavirus infection. Along with other constitutively expressed host cellular factors with antiviral activity, these proteins (hereafter referred to as “restriction factors”) target different steps of the viral cycle, including viral entry, genome transcription and replication, and virion egress. In reaction to this, bunyaviruses have developed strategies to circumvent this antiviral response, by avoiding cellular recognition of PAMPs, inhibiting IFN production or interfering with the IFN-mediated response. Herein, we review the current knowledge on host cellular factors that were shown to restrict infections by bunyaviruses. Moreover, we focus on the strategies developed by bunyaviruses in order to escape the antiviral state developed by the infected cells.
Collapse
|
8
|
Zhang X, Sun K, Liang Y, Wang S, Wu K, Li Z. Development of Rice Stripe Tenuivirus Minireplicon Reverse Genetics Systems Suitable for Analyses of Viral Replication and Intercellular Movement. Front Microbiol 2021; 12:655256. [PMID: 33833749 PMCID: PMC8021733 DOI: 10.3389/fmicb.2021.655256] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 02/19/2021] [Indexed: 12/18/2022] Open
Abstract
Rice stripe virus (RSV), a tenuivirus with four negative-sense/ambisense genome segments, is one of the most devastating viral pathogens affecting rice production in many Asian countries. Despite extensive research, our understanding of RSV infection cycles and pathogenesis has been severely impaired by the lack of reverse genetics tools. In this study, we have engineered RSV minireplicon (MR)/minigenome cassettes with reporter genes substituted for the viral open reading frames in the negative-sense RNA1 or the ambisense RNA2-4 segments. After delivery to Nicotiana benthamiana leaves via agroinfiltration, MR reporter gene expression was detected only when the codon-optimized large viral RNA polymerase protein (L) was coexpressed with the nucleocapsid (N) protein. MR activity was also critically dependent on the coexpressed viral suppressors of RNA silencing, but ectopic expression of the RSV-encoded NS3 silencing suppressor drastically decreased reporter gene expression. We also developed intercellular movement-competent MR systems with the movement protein expressed either in cis from an RNA4-based MR or in trans from a binary plasmid. Finally, we generated multicomponent replicon systems by expressing the N and L proteins directly from complementary-sense RNA1 and RNA3 derivatives, which enhanced reporter gene expression, permitted autonomous replication and intercellular movement, and reduced the number of plasmids required for delivery. In summary, this work enables reverse genetics analyses of RSV replication, transcription, and cell-to-cell movement and provides a platform for engineering more complex recombinant systems.
Collapse
Affiliation(s)
- Xiaoyan Zhang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Kai Sun
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Yan Liang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Shuo Wang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Kaili Wu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Zhenghe Li
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.,Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect, Zhejiang University, Hangzhou, China.,Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| |
Collapse
|
9
|
Establishment of a Reverse Genetic System of Severe Fever with Thrombocytopenia Syndrome Virus Based on a C4 Strain. Virol Sin 2021; 36:958-967. [PMID: 33721215 DOI: 10.1007/s12250-021-00359-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 01/21/2021] [Indexed: 12/31/2022] Open
Abstract
Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus that causes hemorrhagic fever-like disease (SFTS) in humans with a case fatality rate up to 30%. To date, the molecular biology involved in SFTSV infection remains obscure. There are seven major genotypes of SFTSV (C1-C4 and J1-J3) and previously a reverse genetic system was established on a C3 strain of SFTSV. Here, we reported successfully establishment of a reverse genetics system based on a SFTSV C4 strain. First, we obtained the 5'- and 3'-terminal untranslated region (UTR) sequences of the Large (L), Medium (M) and Small (S) segments of a laboratory-adapted SFTSV C4 strain through rapid amplification of cDNA ends analysis, and developed functional T7 polymerase-based L-, M- and S-segment minigenome assays. Then, full-length cDNA clones were constructed and infectious SFTSV were recovered from co-transfected cells. Viral infectivity, growth kinetics, and viral protein expression profile of the rescued virus were compared with the laboratory-adapted virus. Focus formation assay showed that the size and morphology of the foci formed by the rescued SFTSV were indistinguishable with the laboratory-adapted virus. However, one-step growth curve and nucleoprotein expression analyses revealed the rescued virus replicated less efficiently than the laboratory-adapted virus. Sequence analysis indicated that the difference may be due to the mutations in the laboratory-adapted strain which are more prone to cell culture. The results help us to understand the molecular biology of SFTSV, and provide a useful tool for developing vaccines and antivirals against SFTS.
Collapse
|
10
|
Hulswit RJG, Paesen GC, Bowden TA, Shi X. Recent Advances in Bunyavirus Glycoprotein Research: Precursor Processing, Receptor Binding and Structure. Viruses 2021; 13:353. [PMID: 33672327 PMCID: PMC7926653 DOI: 10.3390/v13020353] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/13/2021] [Accepted: 02/15/2021] [Indexed: 01/04/2023] Open
Abstract
The Bunyavirales order accommodates related viruses (bunyaviruses) with segmented, linear, single-stranded, negative- or ambi-sense RNA genomes. Their glycoproteins form capsomeric projections or spikes on the virion surface and play a crucial role in virus entry, assembly, morphogenesis. Bunyavirus glycoproteins are encoded by a single RNA segment as a polyprotein precursor that is co- and post-translationally cleaved by host cell enzymes to yield two mature glycoproteins, Gn and Gc (or GP1 and GP2 in arenaviruses). These glycoproteins undergo extensive N-linked glycosylation and despite their cleavage, remain associated to the virion to form an integral transmembrane glycoprotein complex. This review summarizes recent advances in our understanding of the molecular biology of bunyavirus glycoproteins, including their processing, structure, and known interactions with host factors that facilitate cell entry.
Collapse
Affiliation(s)
- Ruben J. G. Hulswit
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (R.J.G.H.); (G.C.P.)
| | - Guido C. Paesen
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (R.J.G.H.); (G.C.P.)
| | - Thomas A. Bowden
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (R.J.G.H.); (G.C.P.)
| | - Xiaohong Shi
- MRC-University of Glasgow Centre for Virus Research, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow G61 1QH, UK
| |
Collapse
|
11
|
A Look into Bunyavirales Genomes: Functions of Non-Structural (NS) Proteins. Viruses 2021; 13:v13020314. [PMID: 33670641 PMCID: PMC7922539 DOI: 10.3390/v13020314] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/12/2021] [Accepted: 02/16/2021] [Indexed: 12/13/2022] Open
Abstract
In 2016, the Bunyavirales order was established by the International Committee on Taxonomy of Viruses (ICTV) to incorporate the increasing number of related viruses across 13 viral families. While diverse, four of the families (Peribunyaviridae, Nairoviridae, Hantaviridae, and Phenuiviridae) contain known human pathogens and share a similar tri-segmented, negative-sense RNA genomic organization. In addition to the nucleoprotein and envelope glycoproteins encoded by the small and medium segments, respectively, many of the viruses in these families also encode for non-structural (NS) NSs and NSm proteins. The NSs of Phenuiviridae is the most extensively studied as a host interferon antagonist, functioning through a variety of mechanisms seen throughout the other three families. In addition, functions impacting cellular apoptosis, chromatin organization, and transcriptional activities, to name a few, are possessed by NSs across the families. Peribunyaviridae, Nairoviridae, and Phenuiviridae also encode an NSm, although less extensively studied than NSs, that has roles in antagonizing immune responses, promoting viral assembly and infectivity, and even maintenance of infection in host mosquito vectors. Overall, the similar and divergent roles of NS proteins of these human pathogenic Bunyavirales are of particular interest in understanding disease progression, viral pathogenesis, and developing strategies for interventions and treatments.
Collapse
|
12
|
Entry of Phenuiviruses into Mammalian Host Cells. Viruses 2021; 13:v13020299. [PMID: 33672975 PMCID: PMC7918600 DOI: 10.3390/v13020299] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 12/22/2022] Open
Abstract
Phenuiviridae is a large family of arthropod-borne viruses with over 100 species worldwide. Several cause severe diseases in both humans and livestock. Global warming and the apparent geographical expansion of arthropod vectors are good reasons to seriously consider these viruses potential agents of emerging diseases. With an increasing frequency and number of epidemics, some phenuiviruses represent a global threat to public and veterinary health. This review focuses on the early stage of phenuivirus infection in mammalian host cells. We address current knowledge on each step of the cell entry process, from virus binding to penetration into the cytosol. Virus receptors, endocytosis, and fusion mechanisms are discussed in light of the most recent progress on the entry of banda-, phlebo-, and uukuviruses, which together constitute the three prominent genera in the Phenuiviridae family.
Collapse
|
13
|
Reverse genetics approaches for the development of bunyavirus vaccines. Curr Opin Virol 2020; 44:16-25. [PMID: 32619950 DOI: 10.1016/j.coviro.2020.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/18/2022]
Abstract
The Bunyavirales order is the largest group of RNA viruses, which includes important human and animal pathogens, that cause serious diseases. Licensed vaccines are often not available for many of these pathogens. The establishment of bunyavirus reverse genetics systems has facilitated the generation of recombinant infectious viruses, which have been employed as powerful tools for understanding bunyavirus biology and identifying important virulence factors. Technological advances in this area have enabled the development of novel strategies, including codon-deoptimization, viral genome rearrangement and single-cycle replicable viruses, for the generation of live-attenuated vaccine candidates. In this review, we have summarized the current knowledge of the bunyavirus reverse genetics approaches for the generation of live-attenuated vaccine candidates and their evaluation in animal models.
Collapse
|
14
|
The Andes Orthohantavirus NSs Protein Antagonizes the Type I Interferon Response by Inhibiting MAVS Signaling. J Virol 2020; 94:JVI.00454-20. [PMID: 32321811 DOI: 10.1128/jvi.00454-20] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 04/10/2020] [Indexed: 12/11/2022] Open
Abstract
The small messenger RNA (SmRNA) of the Andes orthohantavirus (ANDV), a rodent-borne member of the Hantaviridae family of viruses of the Bunyavirales order, encodes a multifunctional nucleocapsid (N) protein and for a nonstructural (NSs) protein of unknown function. We have previously shown the expression of the ANDV-NSs, but only in infected cell cultures. In this study, we extend our early findings by confirming the expression of the ANDV-NSs protein in the lungs of experimentally infected golden Syrian hamsters. Next, we show, using a virus-free system, that the ANDV-NSs protein antagonizes the type I interferon (IFN) induction pathway by suppressing signals downstream of the melanoma differentiation-associated protein 5 (MDA5) and the retinoic acid-inducible gene 1 (RIG-I) and upstream of TBK1. Consistent with this observation, the ANDV-NSs protein antagonized mitochondrial antiviral-signaling protein (MAVS)-induced IFN-β, NF-κB, IFN-regulatory factor 3 (IRF3), and IFN-sensitive response element (ISRE) promoter activity. Results demonstrate that ANDV-NSs binds to MAVS in cells without disrupting the MAVS-TBK-1 interaction. However, in the presence of the ANDV-NSs ubiquitination of MAVS is reduced. In summary, this study provides evidence showing that the ANDV-NSs protein acts as an antagonist of the cellular innate immune system by suppressing MAVS downstream signaling by a yet not fully understand mechanism. Our findings reveal new insights into the molecular regulation of the hosts' innate immune response by the Andes orthohantavirus.IMPORTANCE Andes orthohantavirus (ANDV) is endemic in Argentina and Chile and is the primary etiological agent of hantavirus cardiopulmonary syndrome (HCPS) in South America. ANDV is distinguished from other hantaviruses by its unique ability to spread from person to person. In a previous report, we identified a novel ANDV protein, ANDV-NSs. Until now, ANDV-NSs had no known function. In this new study, we established that ANDV-NSs acts as an antagonist of cellular innate immunity, the first line of defense against invading pathogens, hindering the cellular antiviral response during infection. This study provides novel insights into the mechanisms used by ANDV to establish its infection.
Collapse
|
15
|
Min YQ, Shi C, Yao T, Feng K, Mo Q, Deng F, Wang H, Ning YJ. The Nonstructural Protein of Guertu Virus Disrupts Host Defenses by Blocking Antiviral Interferon Induction and Action. ACS Infect Dis 2020; 6:857-870. [PMID: 32167734 DOI: 10.1021/acsinfecdis.9b00492] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Guertu virus (GTV) is a potentially highly pathogenic bunyavirus newly isolated in China, which is genetically related to the severe fever with thrombocytopenia syndrome virus (SFTSV) and Heartland virus (HRTV), two other emerging life-threatening bunyaviruses. Previous studies suggested that SFTSV and HRTV antagonize the interferon (IFN) system by targeting antiviral signaling proteins in different ways. However, whether and how GTV counteracts the host innate immunity are unclear. Here, we found that GTV strongly inhibits both IFN induction and action through its nonstructural protein (NSs). Different from the NSs of SFTSV and HRTV, GTV NSs (G-NSs) induced the formation of two distinctive cytoplasmic structures, compact inclusion bodies (IBs) and extended filamentous structures (FSs). Protein interaction and colocalization analyses demonstrated that G-NSs interacts with TBK1 (TANK binding kinase-1, the pivotal kinase for IFN induction) and STAT2 (signal transducer and activator of transcription 2, the essential transcription factor for IFN action) and irreversibly sequesters the host proteins into the viral IBs and FSs. Consistently, G-NSs thus inhibited phosphorylation/activation and nuclear translocation of IFN-regulatory factor 3 (IRF3, the substrate of TBK1), diminishing the IFN induction. Furthermore, G-NSs sequestration of STAT2 blocked phosphorylation/activation and nuclear translocation of STAT2, disabling IFN action and host antiviral state establishment. Collectively, this study shows the robust subversion of the two phases of the IFN antiviral system by GTV and unravels the respective molecular mechanisms, exhibiting some notable differences from those employed by SFTSV and HRTV, providing insights into the virus-host interactions and pathogenesis, and probably also benefiting the prevention and treatment of the related infectious diseases in the future.
Collapse
Affiliation(s)
- Yuan-Qin Min
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
| | - Chen Shi
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- The University of Chinese Academy of Sciences, Beijing 101408, China
| | - Ting Yao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- The University of Chinese Academy of Sciences, Beijing 101408, China
| | - Kuan Feng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- The University of Chinese Academy of Sciences, Beijing 101408, China
| | - Qiong Mo
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- The University of Chinese Academy of Sciences, Beijing 101408, China
| | - Fei Deng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
| | - Hualin Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
| | - Yun-Jia Ning
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, Hubei 430071, China
| |
Collapse
|
16
|
Ren F, Zhou M, Deng F, Wang H, Ning YJ. Combinatorial Minigenome Systems for Emerging Banyangviruses Reveal Viral Reassortment Potential and Importance of a Protruding Nucleotide in Genome "Panhandle" for Promoter Activity and Reassortment. Front Microbiol 2020; 11:599. [PMID: 32322247 PMCID: PMC7156889 DOI: 10.3389/fmicb.2020.00599] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/18/2020] [Indexed: 12/25/2022] Open
Abstract
Banyangvirus is a new genus (Phenuiviridae family, Bunyavirales order) that comprises a group of emerging tick-borne viruses with severe fever with thrombocytopenia syndrome virus (SFTSV) and Heartland virus (HRTV) as virulent representatives. As segmented RNA viruses, bunyaviruses may have genome reassortment potential, increasing the concern about new life-threatening bunyavirus emergence. Using a series of combinatory minigenome reporter assays based on transfection and superinfection, we showed that replication machinery proteins of designated banyangviruses can recognize genomic untranslated regions (UTRs) of other banyangviruses and assemble heterogenous minigenomes into functional ribonucleoproteins (RNPs). Moreover, both heterogenous and heterozygous RNPs were efficiently packaged by viral glycoproteins into infectious virus-like particles, manifesting remarkable reassortment potential of banyangviruses. Meanwhile, UTR promoter strength of the three banyangvirus segments appeared to be M > L > S. Secondary structure analysis revealed a conservative non-basepairing protruding nucleotide in the terminal UTR panhandles of M and L (but not S) segments of all banyangviruses and some related phleboviruses (Phlebovirus genus). Furthermore, not only a conserved panhandle region but also the protruding nucleotide proved important for UTR function. Removal of the protruding nucleotide abated M and L UTR activities and compatibilities with heterogenous viral proteins, and introduction of a protruding nucleotide into S panhandle, conversely, enhanced UTR promoter strength and compatibility, revealing the significance of the protruding nucleotide as a new signature of the genomic panhandle structure in both UTR activity and reassortment potential. The study demonstrates not only banyangvirus reassortment potential but also the notable role of the protruding nucleotide in UTR function and reassortment, providing clues to viral evolution and replication mechanisms and perhaps benefiting disease control and prevention in the future.
Collapse
Affiliation(s)
- Fuli Ren
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Min Zhou
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Fei Deng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Hualin Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Yun-Jia Ning
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| |
Collapse
|
17
|
Woelfl F, Léger P, Oreshkova N, Pahmeier F, Windhaber S, Koch J, Stanifer M, Roman Sosa G, Uckeley ZM, Rey FA, Boulant S, Kortekaas J, Wichgers Schreur PJ, Lozach PY. Novel Toscana Virus Reverse Genetics System Establishes NSs as an Antagonist of Type I Interferon Responses. Viruses 2020; 12:v12040400. [PMID: 32260371 PMCID: PMC7232479 DOI: 10.3390/v12040400] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/30/2020] [Accepted: 04/03/2020] [Indexed: 12/13/2022] Open
Abstract
The sand fly-borne Toscana virus (TOSV) is the major cause of human meningoencephalitis in the Mediterranean basin during the summer season. In this work, we have developed a T7 RNA polymerase-driven reverse genetics system to recover infectious particles of a lineage B strain of TOSV. The viral protein pattern and growth properties of the rescued virus (rTOSV) were found to be similar to those of the corresponding wild-type (wt) virus. Using this system, we genetically engineered a TOSV mutant lacking expression of the non-structural protein NSs (rTOSVɸNSs). Unlike rTOSV and the wt virus, rTOSVɸNSs was unable to (i) suppress interferon (IFN)-b messenger RNA induction; and (ii) grow efficiently in cells producing IFN-b. Together, our results highlight the importance of NSs for TOSV in evading the IFN response and provide a comprehensive toolbox to investigate the TOSV life cycle in mammalian and insect host cells, including several novel polyclonal antibodies.
Collapse
Affiliation(s)
- Franziska Woelfl
- CellNetworks Cluster of Excellence, University Hospital Heidelberg, 69120 Heidelberg, Germany; (F.W.); (P.L.); (F.P.); (S.W.); (J.K.); (Z.M.U.)
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Psylvia Léger
- CellNetworks Cluster of Excellence, University Hospital Heidelberg, 69120 Heidelberg, Germany; (F.W.); (P.L.); (F.P.); (S.W.); (J.K.); (Z.M.U.)
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Nadia Oreshkova
- Wageningen Bioveterinary Research, Department of Virology, 8221 RA Lelystad, The Netherlands; (N.O.); (J.K.)
| | - Felix Pahmeier
- CellNetworks Cluster of Excellence, University Hospital Heidelberg, 69120 Heidelberg, Germany; (F.W.); (P.L.); (F.P.); (S.W.); (J.K.); (Z.M.U.)
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Stefan Windhaber
- CellNetworks Cluster of Excellence, University Hospital Heidelberg, 69120 Heidelberg, Germany; (F.W.); (P.L.); (F.P.); (S.W.); (J.K.); (Z.M.U.)
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Jana Koch
- CellNetworks Cluster of Excellence, University Hospital Heidelberg, 69120 Heidelberg, Germany; (F.W.); (P.L.); (F.P.); (S.W.); (J.K.); (Z.M.U.)
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Megan Stanifer
- Center for Integrative Infectious Diseases Research (CIID), Molecular Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Gleyder Roman Sosa
- Structural Virology Unit, Pasteur Institute, 75015 Paris, France; (G.R.S.); (F.A.R.)
| | - Zina M. Uckeley
- CellNetworks Cluster of Excellence, University Hospital Heidelberg, 69120 Heidelberg, Germany; (F.W.); (P.L.); (F.P.); (S.W.); (J.K.); (Z.M.U.)
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Felix A. Rey
- Structural Virology Unit, Pasteur Institute, 75015 Paris, France; (G.R.S.); (F.A.R.)
| | - Steeve Boulant
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
| | - Jeroen Kortekaas
- Wageningen Bioveterinary Research, Department of Virology, 8221 RA Lelystad, The Netherlands; (N.O.); (J.K.)
- Laboratory of Virology, Wageningen University, 6708 PB Wageningen, The Netherlands
| | - Paul J. Wichgers Schreur
- Wageningen Bioveterinary Research, Department of Virology, 8221 RA Lelystad, The Netherlands; (N.O.); (J.K.)
- Correspondence: (P.J.W.S.); (P.-Y.L.)
| | - Pierre-Yves Lozach
- CellNetworks Cluster of Excellence, University Hospital Heidelberg, 69120 Heidelberg, Germany; (F.W.); (P.L.); (F.P.); (S.W.); (J.K.); (Z.M.U.)
- Center for Integrative Infectious Diseases Research (CIID), Virology, University Hospital Heidelberg, 69120 Heidelberg, Germany;
- INRAE, EPHE, Viral Infections and Comparative Pathology (IVPC), University Claude Bernard Lyon1, University of Lyon, UMR754, 69007 Lyon, France
- Correspondence: (P.J.W.S.); (P.-Y.L.)
| |
Collapse
|
18
|
Ergünay K. Revisiting new tick-associated viruses: what comes next? Future Virol 2020. [DOI: 10.2217/fvl-2019-0149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tick-borne viral infections continue to cause diseases with considerable impact on humans, livestock, companion animals and wildlife. Many lack specific therapeutics and vaccines are available for only a few. Tick-borne viruses will continue to emerge, facilitated by anthroponotic factors related to the modern lifestyle. We persistently identify and are obliged to cope with new examples of emerging tick-borne viral diseases and novel viruses today. Many new strains have been detected in vertebrates and arthropods, some causing severe diseases likely to challenge public and veterinary health. This manuscript aims to provide a narrative overview of recently-described tick-associated viruses, with perspectives on changing paradigms in identification, screening and control.
Collapse
Affiliation(s)
- Koray Ergünay
- Hacettepe University, Faculty of Medicine, Department of Medical Microbiology, Virology Unit, Ankara 06100, Turkey
| |
Collapse
|
19
|
Hallam HJ, Lokugamage N, Ikegami T. Rescue of infectious Arumowot virus from cloned cDNA: Posttranslational degradation of Arumowot virus NSs protein in human cells. PLoS Negl Trop Dis 2019; 13:e0007904. [PMID: 31751340 PMCID: PMC6894884 DOI: 10.1371/journal.pntd.0007904] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 12/05/2019] [Accepted: 11/04/2019] [Indexed: 12/11/2022] Open
Abstract
Rift Valley fever (RVF) is a mosquito-borne zoonotic disease endemic to Africa and the Middle East, affecting both humans and ruminants. There are no licensed vaccines or antivirals available for humans, whereas research using RVF virus (RVFV) is strictly regulated in many countries with safety concerns. Nonpathogenic Arumowot virus (AMTV), a mosquito-borne phlebovirus in Africa, is likely useful for the screening of broad-acting antiviral candidates for phleboviruses including RVFV, as well as a potential vaccine vector for RVF. In this study, we aimed to generate T7 RNA polymerase-driven reverse genetics system for AMTV. We hypothesized that recombinant AMTV (rAMTV) is viable, and AMTV NSs protein is dispensable for efficient replication of rAMTV in type-I interferon (IFN)-incompetent cells, whereas AMTV NSs proteins support robust viral replication in type-I IFN-competent cells. The study demonstrated the rescue of rAMTV and that lacking the NSs gene (rAMTVΔNSs), that expressing green fluorescent protein (GFP) (rAMTV-GFP) or that expressing Renilla luciferase (rAMTV-rLuc) from cloned cDNA. The rAMTV-rLuc and the RVFV rMP12-rLuc showed a similar susceptibility to favipiravir or ribavirin. Interestingly, neither of rAMTV nor rAMTVΔNSs replicated efficiently in human MRC-5 or A549 cells, regardless of the presence of NSs gene. Little accumulation of AMTV NSs protein occurred in those cells, which was restored via treatment with proteasomal inhibitor MG132. In murine MEF or Hepa1-6 cells, rAMTV, but not rAMTVΔNSs, replicated efficiently, with an inhibition of IFN-β gene upregulation. This study showed an establishment of the first reverse genetics for AMTV, a lack of stability of AMTV NSs proteins in human cells, and an IFN-β gene antagonist function of AMTV NSs proteins in murine cells. The AMTV can be a nonpathogenic surrogate model for studying phleboviruses including RVFV.
Collapse
Affiliation(s)
- Hoai J. Hallam
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Nandadeva Lokugamage
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Tetsuro Ikegami
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
- Sealy Institute for Vaccine Sciences, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
- Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
- * E-mail:
| |
Collapse
|
20
|
Immune Modulation and Immune-Mediated Pathogenesis of Emerging Tickborne Banyangviruses. Vaccines (Basel) 2019; 7:vaccines7040125. [PMID: 31547199 PMCID: PMC6963857 DOI: 10.3390/vaccines7040125] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 12/21/2022] Open
Abstract
In the last decade, the emergence of several, novel tickborne viruses have caused significant disease in humans. Of interest are the tickborne banyangviruses: Severe fever with thrombocytopenia syndrome virus (SFTSV), Heartland virus (HRTV), and Guertu virus (GTV). SFTSV and HRTV infection in humans cause viral hemorrhagic fever-like disease leading to mortality rates ranging from 6–30% of the cases. The systemic inflammatory response syndrome (SIRS) associated with SFTSV infection is hypothesized to contribute significantly to pathology seen in patients. Despite the severe disease caused by HRTV and SFTSV, there are no approved therapeutics or vaccines. Investigation of the immune response during and following infection is critical to the generation of fully protective vaccines and/or supportive treatments, and overall understanding of viral immune evasion mechanisms may aid in the development of a new class of therapeutics.
Collapse
|
21
|
Petersen A, Rosenstierne MW, Rasmussen M, Fuursted K, Nielsen HV, O'Brien Andersen L, Bødker R, Fomsgaard A. Field samplings of Ixodes ricinus ticks from a tick-borne encephalitis virus micro-focus in Northern Zealand, Denmark. Ticks Tick Borne Dis 2019; 10:1028-1032. [PMID: 31151922 DOI: 10.1016/j.ttbdis.2019.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 04/25/2019] [Accepted: 05/17/2019] [Indexed: 12/01/2022]
Abstract
In 2008-2009 a tick-borne encephalitis virus (TBEV) micro-focus was detected in Northern Zealand, Denmark. No new cases of TBE with an epidemiological link to Northern Zealand has been reported since. Here we undertook to investigate Ixodes ricinus ticks from this endemic micro-focus in 2016 and 2017. In addition to TBEV, I. ricinus ticks may host other pathogens that include Borrelia spp., Babesia spp., Rickettsia spp. and Neoehrlichia mikurensis, together with various endosymbiont microorganisms. To detect multiple organisms we used a metagenomics PanVirus microarray and next-generation sequencing to examine the persistence and evolution of other emerging viruses, bacteria and parasites. Here we report the rise and fall of the Danish TBEV micro-focus in Northern Zealand. However, we identify for the first time in Danish I. ricinus ticks the presence of Uukuniemi virus in addition to a tick-borne phlebovirus and a range of bacteria.
Collapse
Affiliation(s)
- Andreas Petersen
- European Program for Public Health Microbiology Training (EUPHEM), European Centre for Disease Prevention and Control, (ECDC), Solna, Sweden; Virus Research and Development Laboratory, Department of Virus and Microbiological Special Diagnosis, Statens Serum Institut, Copenhagen, Denmark; Bacteria, Parasites and Fungi, Infection Preparedness, Statens Serum Institut, Copenhagen, Denmark.
| | - Maiken Worsøe Rosenstierne
- Virus Research and Development Laboratory, Department of Virus and Microbiological Special Diagnosis, Statens Serum Institut, Copenhagen, Denmark
| | - Morten Rasmussen
- Virus Research and Development Laboratory, Department of Virus and Microbiological Special Diagnosis, Statens Serum Institut, Copenhagen, Denmark
| | - Kurt Fuursted
- Bacteria, Parasites and Fungi, Infection Preparedness, Statens Serum Institut, Copenhagen, Denmark
| | - Henrik Vedel Nielsen
- Bacteria, Parasites and Fungi, Infection Preparedness, Statens Serum Institut, Copenhagen, Denmark
| | - Lee O'Brien Andersen
- Bacteria, Parasites and Fungi, Infection Preparedness, Statens Serum Institut, Copenhagen, Denmark
| | - René Bødker
- DTU National Veterinary Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Anders Fomsgaard
- Virus Research and Development Laboratory, Department of Virus and Microbiological Special Diagnosis, Statens Serum Institut, Copenhagen, Denmark; Infectious Disease Research Unit, Clinical Institute, University of Southern Denmark, Odense, Denmark
| |
Collapse
|
22
|
Hoffmann AB, Mazelier M, Léger P, Lozach PY. Deciphering Virus Entry with Fluorescently Labeled Viral Particles. Methods Mol Biol 2019; 1836:159-183. [PMID: 30151573 DOI: 10.1007/978-1-4939-8678-1_8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
To infect host cells, viruses have to gain access to the intracellular compartment. The infection process starts with the attachment of viruses to the cell surface. Then a complex series of events, highly dynamic, tightly intricate, and often hard to investigate, follows. This includes virus displacement at the plasma membrane, binding to receptors, signaling, internalization, and release of the viral genome and material into the cytosol. In the past decades, the emergence of sensitive, accurate fluorescence-based technologies has opened new perspectives of investigations in the field. Visualization of single viral particles in fixed and living cells as well as quantification of each virus entry step has been made possible. Here we describe the procedure to fluorescently label viral particles. We also illustrate how to use this powerful tool to decipher the entry of viruses with the most recent fluorescence-based techniques such as high-speed confocal and total internal reflection microscopy, flow cytometry, and fluorimetry.
Collapse
Affiliation(s)
- Anja B Hoffmann
- From CellNetworks Cluster of Excellence and Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Magalie Mazelier
- From CellNetworks Cluster of Excellence and Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Psylvia Léger
- From CellNetworks Cluster of Excellence and Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Pierre-Yves Lozach
- From CellNetworks Cluster of Excellence and Department of Infectious Diseases, Virology, University Hospital Heidelberg, Heidelberg, Germany.
| |
Collapse
|
23
|
M Segment-Based Minigenomes and Virus-Like Particle Assays as an Approach To Assess the Potential of Tick-Borne Phlebovirus Genome Reassortment. J Virol 2019; 93:JVI.02068-18. [PMID: 30567991 PMCID: PMC6401446 DOI: 10.1128/jvi.02068-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 12/14/2018] [Indexed: 12/20/2022] Open
Abstract
Bunyaviruses have a tripartite negative-sense RNA genome. Due to the segmented nature of these viruses, if two closely related viruses coinfect the same host or vector cell, it is possible that RNA segments from either of the two parental viruses will be incorporated into progeny virions to give reassortant viruses. Little is known about the ability of tick-borne phleboviruses to reassort. The present study describes the development of minigenome assays for the tick-borne viruses Uukuniemi phlebovirus (UUKV) and Heartland phlebovirus (HRTV). We used these minigenome assays in conjunction with the existing minigenome system of severe fever with thrombocytopenia syndrome (SFTS) phlebovirus (SFTSV) to assess the abilities of viral N and L proteins to recognize, transcribe, and replicate the M segment-based minigenome of a heterologous virus. The highest minigenome activity was detected with the M segment-based minigenomes of cognate viruses. However, our findings indicate that several combinations utilizing N and L proteins of heterologous viruses resulted in M segment minigenome activity. This suggests that the M segment untranslated regions (UTRs) are recognized as functional promoters of transcription and replication by the N and L proteins of related viruses. Further, virus-like particle assays demonstrated that HRTV glycoproteins can package UUKV and SFTSV S and L segment-based minigenomes. Taken together, these results suggest that coinfection with these viruses could lead to the generation of viable reassortant progeny. Thus, the tools developed in this study could aid in understanding the role of genome reassortment in the evolution of these emerging pathogens in an experimental setting.IMPORTANCE In recent years, there has been a large expansion in the number of emerging tick-borne viruses that are assigned to the Phlebovirus genus. Bunyaviruses have a tripartite segmented genome, and infection of the same host cell by two closely related bunyaviruses can, in theory, result in eight progeny viruses with different genome segment combinations. We used genome analogues expressing reporter genes to assess the abilities of Phlebovirus nucleocapsid protein and RNA-dependent RNA polymerase to recognize the untranslated region of a genome segment of a related phlebovirus, and we used virus-like particle assays to assess whether viral glycoproteins can package genome analogues of related phleboviruses. Our results provide strong evidence that these emerging pathogens could reassort their genomes if they were to meet in nature in an infected host or vector. This reassortment process could result in viruses with new pathogenic properties.
Collapse
|
24
|
Ter Horst S, Conceição-Neto N, Neyts J, Rocha-Pereira J. Structural and functional similarities in bunyaviruses: Perspectives for pan-bunya antivirals. Rev Med Virol 2019; 29:e2039. [PMID: 30746831 PMCID: PMC7169261 DOI: 10.1002/rmv.2039] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 11/29/2018] [Accepted: 01/17/2019] [Indexed: 01/03/2023]
Abstract
The order of Bunyavirales includes numerous (re)emerging viruses that collectively have a major impact on human and animal health worldwide. There are no vaccines for human use or antiviral drugs available to prevent or treat infections with any of these viruses. The development of efficacious and safe drugs and vaccines is a pressing matter. Ideally, such antivirals possess pan‐bunyavirus antiviral activity, allowing the containment of every bunya‐related threat. The fact that many bunyaviruses need to be handled in laboratories with biosafety level 3 or 4, the great variety of species and the frequent emergence of novel species complicate such efforts. We here examined the potential druggable targets of bunyaviruses, together with the level of conservation of their biological functions, structure, and genetic similarity by means of heatmap analysis. In the light of this, we revised the available models and tools currently available, pointing out directions for antiviral drug discovery.
Collapse
Affiliation(s)
- Sebastiaan Ter Horst
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven, Leuven, Belgium
| | - Nádia Conceição-Neto
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Clinical and Epidemiological Virology, KU Leuven, Leuven, Belgium
| | - Johan Neyts
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven, Leuven, Belgium
| | - Joana Rocha-Pereira
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven, Leuven, Belgium
| |
Collapse
|
25
|
NSs Protein of Sandfly Fever Sicilian Phlebovirus Counteracts Interferon (IFN) Induction by Masking the DNA-Binding Domain of IFN Regulatory Factor 3. J Virol 2018; 92:JVI.01202-18. [PMID: 30232186 PMCID: PMC6232482 DOI: 10.1128/jvi.01202-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 09/13/2018] [Indexed: 12/25/2022] Open
Abstract
Sandfly fever Sicilian virus (SFSV) is one of the most widespread and frequently identified members of the genus Phlebovirus (order Bunyavirales, family Phenuiviridae) infecting humans. Being transmitted by Phlebotomus sandflies, SFSV causes a self-limiting, acute, often incapacitating febrile disease ("sandfly fever," "Pappataci fever," or "dog disease") that has been known since at least the beginning of the 20th century. We show that, similarly to other pathogenic phleboviruses, SFSV suppresses the induction of the antiviral type I interferon (IFN) system in an NSs-dependent manner. SFSV NSs interfered with the TBK1-interferon regulatory factor 3 (IRF3) branch of the RIG-I signaling pathway but not with NF-κB activation. Consistently, we identified IRF3 as a host interactor of SFSV NSs. In contrast to IRF3, neither the IFN master regulator IRF7 nor any of the related transcription factors IRF2, IRF5, and IRF9 were bound by SFSV NSs. In spite of this specificity for IRF3, NSs did not inhibit its phosphorylation, dimerization, or nuclear accumulation, and the interaction was independent of the IRF3 activation or multimerization state. In further studies, we identified the DNA-binding domain of IRF3 (amino acids 1 to 113) as sufficient for NSs binding and found that SFSV NSs prevented the association of activated IRF3 with the IFN-β promoter. Thus, unlike highly virulent phleboviruses, which either destroy antiviral host factors or sequester whole signaling chains into inactive aggregates, SFSV modulates type I IFN induction by directly masking the DNA-binding domain of IRF3.IMPORTANCE Phleboviruses are receiving increased attention due to the constant discovery of new species and the ongoing spread of long-known members of the genus. Outbreaks of sandfly fever were reported in the 19th century, during World War I, and during World War II. Currently, SFSV is recognized as one of the most widespread phleboviruses, exhibiting high seroprevalence rates in humans and domestic animals and causing a self-limiting but incapacitating disease predominantly in immunologically naive troops and travelers. We show how the nonstructural NSs protein of SFSV counteracts the upregulation of the antiviral interferon (IFN) system. SFSV NSs specifically inhibits promoter binding by IFN transcription factor 3 (IRF3), a molecular strategy which is unique among phleboviruses and, to our knowledge, among human pathogenic RNA viruses in general. This IRF3-specific and stoichiometric mechanism, greatly distinct from the ones exhibited by the highly virulent phleboviruses, correlates with the intermediate level of pathogenicity of SFSV.
Collapse
|
26
|
Papa A, Zelená H, Papadopoulou E, Mrázek J. Uukuniemi virus, Czech Republic. Ticks Tick Borne Dis 2018; 9:1129-1132. [PMID: 29699908 DOI: 10.1016/j.ttbdis.2018.04.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 10/17/2022]
Abstract
Following the identification of severe fever with thrombocytopenia syndrome and Heartland viruses, the interest on tick-borne phleboviruses has increased rapidly. Uukuniemi virus has been proposed as a model for tick-borne phleboviruses. However, the number of available sequences is limited. In the current study we performed whole-genome sequencing on two Uukuniemi viral strains isolated in 2000 and 2004 from Ixodes ricinus ticks in the Czech Republic. Both strains cluster together with Potepli63 strain isolated in the country in 1963. Although the Czech strains were isolated many years apart, a high identity was seen at the nucleotide and amino acid levels, suggesting that UUKV has a relatively stable genome.
Collapse
Affiliation(s)
- Anna Papa
- Department of Microbiology, Medical School, Aristotle University of Thessaloniki, Greece.
| | - Hana Zelená
- Department of Virology, Institute of Public Health, Ostrava, Czech Republic; University of Defence, Faculty of Military Health Sciences, Hradec Králové, Czech Republic
| | - Elpida Papadopoulou
- Department of Microbiology, Medical School, Aristotle University of Thessaloniki, Greece
| | - Jakub Mrázek
- Department of Molecular Biology, Institute of Public Health, Ostrava, Czech Republic
| |
Collapse
|
27
|
Mapping of Transcription Termination within the S Segment of SFTS Phlebovirus Facilitated Generation of NSs Deletant Viruses. J Virol 2017; 91:JVI.00743-17. [PMID: 28592543 PMCID: PMC5533932 DOI: 10.1128/jvi.00743-17] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 05/31/2017] [Indexed: 12/15/2022] Open
Abstract
SFTS phlebovirus (SFTSV) is an emerging tick-borne bunyavirus that was first reported in China in 2009. Here we report the generation of a recombinant SFTSV (rHB29NSsKO) that cannot express the viral nonstructural protein (NSs) upon infection of cells in culture. We show that rHB29NSsKO replication kinetics are greater in interferon (IFN)-incompetent cells and that the virus is unable to suppress IFN induced in response to viral replication. The data confirm for the first time in the context of virus infection that NSs acts as a virally encoded IFN antagonist and that NSs is dispensable for virus replication. Using 3' rapid amplification of cDNA ends (RACE), we mapped the 3' end of the N and NSs mRNAs, showing that the mRNAs terminate within the coding region of the opposite open reading frame. We show that the 3' end of the N mRNA terminates upstream of a 5'-GCCAGCC-3' motif present in the viral genomic RNA. With this knowledge, and using virus-like particles, we could demonstrate that the last 36 nucleotides of the NSs open reading frame (ORF) were needed to ensure the efficient termination of the N mRNA and were required for recombinant virus rescue. We demonstrate that it is possible to recover viruses lacking NSs (expressing just a 12-amino-acid NSs peptide or encoding enhanced green fluorescent protein [eGFP]) or an NSs-eGFP fusion protein in the NSs locus. This opens the possibility for further studies of NSs and potentially the design of attenuated viruses for vaccination studies.IMPORTANCE SFTS phlebovirus (SFTSV) and related tick-borne viruses have emerged globally since 2009. SFTSV has been shown to cause severe disease in humans. For bunyaviruses, it has been well documented that the nonstructural protein (NSs) enables the virus to counteract the human innate antiviral defenses and that NSs is one of the major determinants of virulence in infection. Therefore, the use of reverse genetics systems to engineer viruses lacking NSs is an attractive strategy to rationally attenuate bunyaviruses. Here we report the generation of several recombinant SFTS viruses that cannot express the NSs protein or have the NSs open reading frame replaced with a reporter gene. These viruses cannot antagonize the mammalian interferon (IFN) response mounted to virus infection. The generation of NSs-lacking viruses was achieved by mapping the transcriptional termination of two S-segment-derived subgenomic mRNAs, which revealed that transcription termination occurs upstream of a 5'-GCCAGCC-3' motif present in the virus genomic S RNA.
Collapse
|
28
|
Differential Antagonism of Human Innate Immune Responses by Tick-Borne Phlebovirus Nonstructural Proteins. mSphere 2017; 2:mSphere00234-17. [PMID: 28680969 PMCID: PMC5489658 DOI: 10.1128/msphere.00234-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 06/05/2017] [Indexed: 12/24/2022] Open
Abstract
In recent years, several newly discovered tick-borne viruses causing a wide spectrum of diseases in humans have been ascribed to the Phlebovirus genus of the Bunyaviridae family. The nonstructural protein (NSs) of bunyaviruses is the main virulence factor and interferon (IFN) antagonist. We studied the molecular mechanisms of IFN antagonism employed by the NSs proteins of human apathogenic Uukuniemi virus (UUKV) and those of Heartland virus (HRTV) and severe fever with thrombocytopenia syndrome virus (SFTSV), both of which cause severe disease. Using reporter assays, we found that UUKV NSs weakly inhibited the activation of the beta interferon (IFN-β) promoter and response elements. UUKV NSs weakly antagonized human IFN-β promoter activation through a novel interaction with mitochondrial antiviral-signaling protein (MAVS), confirmed by coimmunoprecipitation and confocal microscopy studies. HRTV NSs efficiently antagonized both IFN-β promoter activation and type I IFN signaling pathways through interactions with TBK1, preventing its phosphorylation. HRTV NSs exhibited diffused cytoplasmic localization. This is in comparison to the inclusion bodies formed by SFTSV NSs. HRTV NSs also efficiently interacted with STAT2 and impaired IFN-β-induced phosphorylation but did not affect STAT1 or its translocation to the nucleus. Our results suggest that a weak interaction between STAT1 and HRTV or SFTSV NSs may explain their inability to block type II IFN signaling efficiently, thus enabling the activation of proinflammatory responses that lead to severe disease. Our findings offer insights into how pathogenicity may be linked to the capacity of NSs proteins to block the innate immune system and illustrate the plethora of viral immune evasion strategies utilized by emerging phleboviruses. IMPORTANCE Since 2011, there has been a large expansion in the number of emerging tick-borne viruses that have been assigned to the Phlebovirus genus. Heartland virus (HRTV) and SFTS virus (SFTSV) were found to cause severe disease in humans, unlike other documented tick-borne phleboviruses such as Uukuniemi virus (UUKV). Phleboviruses encode nonstructural proteins (NSs) that enable them to counteract the human innate antiviral defenses. We assessed how these proteins interacted with the innate immune system. We found that UUKV NSs engaged with innate immune factors only weakly, at one early step. However, the viruses that cause more severe disease efficiently disabled the antiviral response by targeting multiple components at several stages across the innate immune induction and signaling pathways. Our results suggest a correlation between the efficiency of the virus protein/host interaction and severity of disease.
Collapse
|
29
|
Papa A, Kontana A, Tsioka K, Saratsis A, Sotiraki S. Novel phlebovirus detected in Haemaphysalis parva ticks in a Greek island. Ticks Tick Borne Dis 2017; 8:157-160. [DOI: 10.1016/j.ttbdis.2016.10.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 10/17/2016] [Accepted: 10/25/2016] [Indexed: 11/25/2022]
|
30
|
Hedil M, Kormelink R. Viral RNA Silencing Suppression: The Enigma of Bunyavirus NSs Proteins. Viruses 2016; 8:v8070208. [PMID: 27455310 PMCID: PMC4974542 DOI: 10.3390/v8070208] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 12/21/2022] Open
Abstract
The Bunyaviridae is a family of arboviruses including both plant- and vertebrate-infecting representatives. The Tospovirus genus accommodates plant-infecting bunyaviruses, which not only replicate in their plant host, but also in their insect thrips vector during persistent propagative transmission. For this reason, they are generally assumed to encounter antiviral RNA silencing in plants and insects. Here we present an overview on how tospovirus nonstructural NSs protein counteracts antiviral RNA silencing in plants and what is known so far in insects. Like tospoviruses, members of the related vertebrate-infecting bunyaviruses classified in the genera Orthobunyavirus, Hantavirus and Phlebovirus also code for a NSs protein. However, for none of them RNA silencing suppressor activity has been unambiguously demonstrated in neither vertebrate host nor arthropod vector. The second part of this review will briefly describe the role of these NSs proteins in modulation of innate immune responses in mammals and elaborate on a hypothetical scenario to explain if and how NSs proteins from vertebrate-infecting bunyaviruses affect RNA silencing. If so, why this discovery has been hampered so far.
Collapse
Affiliation(s)
- Marcio Hedil
- Laboratory of Virology, Department of Plant Sciences, Wageningen University, Wageningen, 6708PB, The Netherlands.
| | - Richard Kormelink
- Laboratory of Virology, Department of Plant Sciences, Wageningen University, Wageningen, 6708PB, The Netherlands.
| |
Collapse
|
31
|
Abstract
In the last decade, novel tick-borne pathogenic phleboviruses in the family Bunyaviridae, all closely related to Uukuniemi virus (UUKV), have emerged on different continents. To reproduce the tick-mammal switch in vitro, we first established a reverse genetics system to rescue UUKV with a genome close to that of the authentic virus isolated from the Ixodes ricinus tick reservoir. The IRE/CTVM19 and IRE/CTVM20 cell lines, both derived from I. ricinus, were susceptible to the virus rescued from plasmid DNAs and supported production of the virus over many weeks, indicating that infection was persistent. The glycoprotein GC was mainly highly mannosylated on tick cell-derived viral progeny. The second envelope viral protein, GN, carried mostly N-glycans not recognized by the classical glycosidases peptide-N-glycosidase F (PNGase F) and endoglycosidase H (Endo H). Treatment with β-mercaptoethanol did not impact the apparent molecular weight of GN. On viruses originating from mammalian BHK-21 cells, GN glycosylations were exclusively sensitive to PNGase F, and the electrophoretic mobility of the protein was substantially slower after the reduction of disulfide bonds. Furthermore, the amount of viral nucleoprotein per focus forming unit differed markedly whether viruses were produced in tick or BHK-21 cells, suggesting a higher infectivity for tick cell-derived viruses. Together, our results indicate that UUKV particles derived from vector tick cells have glycosylation and structural specificities that may influence the initial infection in mammalian hosts. This study also highlights the importance of working with viruses originating from arthropod vector cells in investigations of the cell biology of arbovirus transmission and entry into mammalian hosts. IMPORTANCE Tick-borne phleboviruses represent a growing threat to humans globally. Although ticks are important vectors of infectious emerging diseases, previous studies have mainly involved virus stocks produced in mammalian cells. This limitation tends to minimize the importance of host alternation in virus transmission to humans and initial infection at the molecular level. With this study, we have developed an in vitro tick cell-based model that allows production of the tick-borne Uukuniemi virus to high titers. Using this system, we found that virions derived from tick cells have specific structural properties and N-glycans that may enhance virus infectivity for mammalian cells. By shedding light on molecular aspects of tick-derived viral particles, our data illustrate the importance of considering the host switch in studying early virus-mammalian receptor/cell interactions. The information gained here lays the basis for future research on not only tick-borne phleboviruses but also all viruses and other pathogens transmitted by ticks.
Collapse
|
32
|
Ly HJ, Ikegami T. Rift Valley fever virus NSs protein functions and the similarity to other bunyavirus NSs proteins. Virol J 2016; 13:118. [PMID: 27368371 PMCID: PMC4930582 DOI: 10.1186/s12985-016-0573-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 06/23/2016] [Indexed: 12/31/2022] Open
Abstract
Rift Valley fever is a mosquito-borne zoonotic disease that affects both ruminants and humans. The nonstructural (NS) protein, which is a major virulence factor for Rift Valley fever virus (RVFV), is encoded on the S-segment. Through the cullin 1-Skp1-Fbox E3 ligase complex, the NSs protein promotes the degradation of at least two host proteins, the TFIIH p62 and the PKR proteins. NSs protein bridges the Fbox protein with subsequent substrates, and facilitates the transfer of ubiquitin. The SAP30-YY1 complex also bridges the NSs protein with chromatin DNA, affecting cohesion and segregation of chromatin DNA as well as the activation of interferon-β promoter. The presence of NSs filaments in the nucleus induces DNA damage responses and causes cell-cycle arrest, p53 activation, and apoptosis. Despite the fact that NSs proteins have poor amino acid similarity among bunyaviruses, the strategy utilized to hijack host cells are similar. This review will provide and summarize an update of recent findings pertaining to the biological functions of the NSs protein of RVFV as well as the differences from those of other bunyaviruses.
Collapse
Affiliation(s)
- Hoai J Ly
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Tetsuro Ikegami
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, TX, USA. .,The Sealy Center for Vaccine Development, The University of Texas Medical Branch at Galveston, Galveston, TX, USA. .,The Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch at Galveston, Galveston, TX, USA.
| |
Collapse
|
33
|
Wuerth JD, Weber F. Phleboviruses and the Type I Interferon Response. Viruses 2016; 8:v8060174. [PMID: 27338447 PMCID: PMC4926194 DOI: 10.3390/v8060174] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Revised: 06/15/2016] [Accepted: 06/20/2016] [Indexed: 12/16/2022] Open
Abstract
The genus Phlebovirus of the family Bunyaviridae contains a number of emerging virus species which pose a threat to both human and animal health. Most prominent members include Rift Valley fever virus (RVFV), sandfly fever Naples virus (SFNV), sandfly fever Sicilian virus (SFSV), Toscana virus (TOSV), Punta Toro virus (PTV), and the two new members severe fever with thrombocytopenia syndrome virus (SFTSV) and Heartland virus (HRTV). The nonstructural protein NSs is well established as the main phleboviral virulence factor in the mammalian host. NSs acts as antagonist of the antiviral type I interferon (IFN) system. Recent progress in the elucidation of the molecular functions of a growing list of NSs proteins highlights the astonishing variety of strategies employed by phleboviruses to evade the IFN system.
Collapse
Affiliation(s)
- Jennifer Deborah Wuerth
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen 35392, Germany.
| | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, Giessen 35392, Germany.
| |
Collapse
|
34
|
Conserved Endonuclease Function of Hantavirus L Polymerase. Viruses 2016; 8:v8050108. [PMID: 27144576 PMCID: PMC4885073 DOI: 10.3390/v8050108] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 04/18/2016] [Accepted: 04/19/2016] [Indexed: 11/17/2022] Open
Abstract
Hantaviruses are important emerging pathogens belonging to the Bunyaviridae family. Like other segmented negative strand RNA viruses, the RNA-dependent RNA polymerase (RdRp) also known as L protein of hantaviruses lacks an intrinsic "capping activity". Hantaviruses therefore employ a "cap snatching" strategy acquiring short 5' RNA sequences bearing 5'cap structures by endonucleolytic cleavage from host cell transcripts. The viral endonuclease activity implicated in cap snatching of hantaviruses has been mapped to the N-terminal domain of the L protein. Using a combination of molecular modeling and structure-function analysis we confirm and extend these findings providing evidence for high conservation of the L endonuclease between Old and New World hantaviruses. Recombinant hantavirus L endonuclease showed catalytic activity and a defined cation preference shared by other viral endonucleases. Based on the previously reported remarkably high activity of hantavirus L endonuclease, we established a cell-based assay for the hantavirus endonuclase function. The robustness of the assay and its high-throughput compatible format makes it suitable for small molecule drug screens to identify novel inhibitors of hantavirus endonuclease. Based on the high degree of similarity to RdRp endonucleases, some candidate inhibitors may be broadly active against hantaviruses and other emerging human pathogenic Bunyaviruses.
Collapse
|
35
|
Brennan B, Weber F, Kormelink R, Schnettler E, Bouloy M, Failloux AB, Weaver SC, Fazakerley JK, Fragkoudis R, Harris M, Barr JN, Palese P, García-Sastre A, Dalziel RG, Dutia BM, Lowen AC, Steel J, Randall RE, Paul Duprex W, Rice CM, Tesh RB, Murphy FA, Ebihara H, Vasconcelos PFC, Nunes MR, Fooks AR, Smith GL, Goodfellow I, Pappu HR, Lamb RA, Paterson RG, Higgs S, Vanlandingham DL, Dietzgen RG, Stephen Lodmell J, Nichol ST, Daly J, Ullman DE, Plyusnin A, Plyusnina A, Efstathiou S, Hewson R, Tordo N, Cherry S, Boutell C, Hosie MJ, Murcia PR, Neil JC, Palmarini M, Patel AH, Willett BJ, Kohl A, McLauchlan J. In memoriam--Richard M. Elliott (1954-2015). J Gen Virol 2015; 96:1975-1978. [PMID: 26315040 DOI: 10.1099/jgv.0.000241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- Benjamin Brennan
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Friedemann Weber
- Institute for Virology, FB10 - Veterinary Medicine, Justus-Liebig University, 35392 Gießen, Germany
| | - Richard Kormelink
- Laboratory of Virology, Department of Plant Sciences, Wageningen University, 6708 PB Wageningen, The Netherlands
| | - Esther Schnettler
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Michèle Bouloy
- Institut Pasteur, 25-28 rue du Dr Roux, 75724 Paris cedex 15, France
| | | | - Scott C Weaver
- University of Texas Medical Branch, Galveston National Laboratory, Galveston, TX 77555-0610, USA
| | | | | | - Mark Harris
- Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - John N Barr
- Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Peter Palese
- Icahn School of Medicine at Mount Sinai, , New York, NY 10029, USA
| | | | - Robert G Dalziel
- The University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | | | - Anice C Lowen
- Emory University School of Medicine, Rollins Research Center, Atlanta, Georgia, GA 30322, USA
| | - John Steel
- Emory University School of Medicine, Rollins Research Center, Atlanta, Georgia, GA 30322, USA
| | - Richard E Randall
- Biomolecular Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - W Paul Duprex
- Department of Microbiology, Boston University School of Medicine and National Emerging Infectious Diseases Laboratories, Boston University, Boston, MA 02118, USA
| | - Charles M Rice
- Laboratory of Virology & Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Robert B Tesh
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
| | - Frederick A Murphy
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
| | - Hideki Ebihara
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
| | - Pedro F C Vasconcelos
- Seção de Arbovirologia e Febres Haemorrágicas, Instituto Evandro Chagas, Ministério da Saúde, CEP 67030000, Ananindeua, Pará, Brasil
| | - Marcio R Nunes
- Seção de Arbovirologia e Febres Haemorrágicas, Instituto Evandro Chagas, Ministério da Saúde, CEP 67030000, Ananindeua, Pará, Brasil
| | - Anthony R Fooks
- APHA Weybridge, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Geoffrey L Smith
- Division of Virology, Department of Pathology, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK
| | - Ian Goodfellow
- Division of Virology, Department of Pathology, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK
| | - Hanu R Pappu
- Department of Plant Pathology, Washington State University, Pullman, WA 99164, USA
| | - Robert A Lamb
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Reay G Paterson
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Stephen Higgs
- Biosecurity Research Institute, Kansas State University, Manhattan, KS 66506-7600, USA
| | - Dana L Vanlandingham
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, KS 66506, USA
| | | | - J Stephen Lodmell
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Stuart T Nichol
- Viral Special Pathogens Branch, Division of High Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, , Atlanta, GA 30329-4027, USA
| | - Janet Daly
- School of Veterinary Medicine and Science, University of Nottingham, Leicestershire LE12 5RD, UK
| | - Diane E Ullman
- Department of Entomology, University of California, Davis, CA 95616, USA
| | | | | | - Stacey Efstathiou
- National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK
| | - Roger Hewson
- Public Health England - Microbiology Services, , Porton Down, Salisbury SP4 0JG, UK
| | - Noël Tordo
- WHO Collaborative Centre for Arboviruses and Viral Haemorrhagic Fevers, OIE Reference Laboratory for RVFV and CCHFV, Institut Pasteur, 25 rue du Dr Roux, 75724 Paris cedex 15, France
| | - Sara Cherry
- University of Pennsylvania, 304K Lynch Laboratories, Philadelphia, PA 19104, USA
| | - Chris Boutell
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Margaret J Hosie
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Pablo R Murcia
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - James C Neil
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Massimo Palmarini
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Arvind H Patel
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Brian J Willett
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - Alain Kohl
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| | - John McLauchlan
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, Scotland, UK
| |
Collapse
|
36
|
Léger P, Lozach PY. Bunyaviruses: from transmission by arthropods to virus entry into the mammalian host first-target cells. Future Virol 2015. [DOI: 10.2217/fvl.15.52] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The Bunyaviridae constitute a large family of animal RNA viruses distributed worldwide, most members of which are transmitted to vertebrate hosts by arthropods and can cause severe pathologies in humans and livestock. With an increasing number of outbreaks, arthropod-borne bunyaviruses (arbo-bunyaviruses) present a global threat to public health and agricultural productivity. Yet transmission, tropism, receptors and cell entry remain poorly characterized. The focus of this review is on the initial infection of mammalian hosts by arbo-bunyaviruses from cellular and molecular perspectives, with particular attention to the human host. We address current knowledge and advances regarding the identity of the first-target cells and the subsequent processes of entry and penetration into the cytosol. Aspects of the vector-to-host switch that influence the early steps of cell infection in mammalian skin, where incoming particles are introduced by infected arthropods, are also highlighted and discussed.
Collapse
Affiliation(s)
- Psylvia Léger
- CellNetworks – Cluster of Excellence & Department of Infectious Diseases, Virology, University Hospital Heidelberg, D-69120 Heidelberg, Germany
| | - Pierre-Yves Lozach
- CellNetworks – Cluster of Excellence & Department of Infectious Diseases, Virology, University Hospital Heidelberg, D-69120 Heidelberg, Germany
| |
Collapse
|